1. Field of the Invention
The present invention relates to toothbrush mechanisms and more particularly, but not by way of limitation, to a toothbrush having a compartment for containing paste and a drive apparatus for selectively forcing the paste into communication with the bristles.
2. History of the Prior Art
Many attempts have been made to provide a toothbrush which carries its supply of toothpaste in the handle or in a compartment associated with the toothbrush for obvious reasons, not the least of which is portability for travelling or daily teeth brushing at the office or at school.
Another pressing problem is that of inducing children to brush regularly in an attempt to keep their teeth relatively clean between dental office visits.
Further, it is simply unhandy to carry a toothbrush and to have to separately carry a tube of toothpaste, the result of which is very few people brush after every meal, especially after the noontime meal which is usually away from home.
Several of the devices previously attempted were complicated in construction and included pressurized compartments with valves, pumps and flexible bags which required squeezing to force out the paste. Often paste would harden in the orifice between usages and the force available was not sufficient to expel the hardened portion of the paste for the next usage.
Another problem present with the prior art was that due to complexity of construction and operation, such devices were too expensive to get on the market and were practically impossible to clean between usages.
However, one of the prior art devices did teach a more positive method of driving out paste out of the container. That teaching is found in FIGS. 1 through 5 of the patent to Joseph A. Velardi, U.S. Pat. No. 3,868,188, issued Feb. 25, 1975 for a "Brush with Material Supply".
The Velardi device included a rather large cartridge which not only contained a large supply of dentrifice paste, but also contained a rotatable drive rod which caused a disc to follow helical tracks built into the inside surface of the cartridge, the disc serving to force toothpaste out of the opposite end of the cartridge. The problem with the Velardi device is that the cartridge is simply too expensive to manufacture as a throw-away paste supply since the drive components are totally located within the cartridge. On the other hand, the fixed brush components of the Velardi device would be relatively inexpensive. Further, the cartridge serves as a handle for the Velardi toothbrush and therefore must be rigidly constructed which again adds to the cost.